Wirox-coated. Single thread. Countersunk head. Patented ground serrations for quick penetration. For chipboard flooring. Requires no pilot hole or pre-drilling. Requires a TX20 bit. Multi-Head Countersinks Screw Head Flush Single Thread with Ground Serrations for Fast & Accurate Driving Zinc-Plated & Blue-Passivated Hardened Steel Construction WIROX Coated Partially Threaded No Splitting, Even Close to the Edge Deeper Recess for Stronger Bit Hold Screw Point Takes Immediate Hold
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